Tesla will begin production of its first mass-market electric vehicle this month, CEO Elon Musk said Monday, meeting an ambitious goal that was widely questioned in the auto industry.

Tesla will make its first production model of the Model 3 electric car on Friday, Musk said on Twitter. The company will celebrate by holding a "handover party" for the first 30 Model 3 buyers on July 28, he said.

For more than a year, Tesla had targeted summer 2017 for the launch of the Model 3, which carries a base price of $35,000 before tax credits. The car gets 215 miles of range on a battery charge.

The company will manufacture about 100 units of the compact sedan in August and more than 1,500 by September. It "looks like we can reach" 20,000 in December, he said.

A slow ramp-up in production capacity is typical in the auto industry as factory workers learn new assembly tasks, install new equipment and ensure quality.

But the Silicon Valley tech company also warned Monday that a "severe production shortfall" of high-range battery packs undermined its second-quarter production, leading to lower-than-anticipated sales of its current vehicles.

Supply of 100-kilowatt-hour battery packs, which are used in the company's most expensive Model S sedans and Model X crossovers, was insufficient, the company said.

The company said the battery shortfall ended in early June. Production resumed at normal rates after having dipped to 40% below demand.

Tesla also acknowledged that it "has been fairly criticized" for the "production quality and field reliability" of the Model X crossover. But the company said it had "dramatically" improved the process, and "it is now rare for a newly produced Model X to have initial quality problems."

Despite those hurdles, Musk bragged that the Model 3 is two weeks ahead of schedule.

Achieving the goal for the beginning of production could be viewed as a reflection of Tesla's growing capability as a manufacturer. The company has missed many such targets in the past, and some analysts believed production wouldn't start until 2018.

Still, Tesla's long-term ability to keep up with demand remains in question. Orders placed today on the Model 3 won't be fulfilled until mid-2018 "or later," Tesla says. That's in part because the company has already received several hundred thousand refundable deposits for the vehicle.

Meanwhile, rival automakers are lining up competitors. General Motors is already selling the Chevrolet Bolt electric car at a similar price with better range.

Tesla continues to sell the Model S and Model X, both luxury models that can cost more than $100,000.

The company said second-quarter sales of those vehicles totaled more than 22,000.

The consensus projection among analysts was that Tesla sold 24,200 vehicles in the second quarter, according to Evercore ISI. The company does not report monthly sales, unlike the rest of the industry.